This invention relates to a water purification device. In particular, but not exclusively, the invention relates to a collapsible drinking bottle including a filter element for filtering fluid when filling the bottle.
In recent years there has been an increase in the demand for bottled water. One of the reasons for this increase in demand is the public's lack of confidence in the water quality of public water management systems. For this reason it is common practice to buy bottled water instead of drinking water from a tap. This is not only common practice when travelling to other cities or countries but also in local environments. For example, many people prefer to filter their own household tap water before drinking it. This is typically done by purification devices installed directly on the water supply piping or tap, or by purification devices in the form of containers or jugs from which the filtered water is then dispensed as required.
A problem with the above devices for filtering water is that it is not suitable for use other than domestic use. The design of these purification devices do not allow them to be used on the move. To address this shortcoming, several attempts have been made to design a purification device which can be used when travelling or simply be taken with when leaving the house.
One purification device that has been suggested is a flexible bag which has a filter element for filtering water when filling it. Although the bag can be easily transported it is particularly challenging drinking from it. Without any rigidity to the sidewalls of the bag it is generally difficult to lift it to dispense water. As a result, water is often spilled when trying to drink or pour water from the bag.
Another purification device that has been proposed is in the form of a bottle including a removable cap that carries a filter device. While the bottle has rigid sidewalls which facilitates holding and lifting of the bottle, the drinking action required to dispense water from the bottle is unnatural. This is largely due to the fact that the filter element is located in the water flow path both when filling the bottle and when dispensing water therefrom. By locating the filtering element in the water flow path when dispensing water a pressure has to be applied to the nozzle in order to obtain a sufficiently high flow rate. As a result, a user is typically required to apply a negative pressure to the nozzle by sucking thereon in order to get a desired flow rate. Alternatively, a positive pressure could also be applied to the bottle in order to squirt a jet of water from the nozzle. A person familiar with this type of purification device will know that it is inconvenient to use seeing that it does not allow for a natural drinking action.
It is an object of this invention to alleviate at least some of the problems experienced with existing purification devices.
It is a further object of this invention to provide a purification device that will be a useful alternative to existing purification devices.